One type of feature that is available to some telephone users is call screening. For example, a first party who does not wish to receive calls from a second party may have a telephone service provider detect and prevent any call attempts inbound from the second party. This service is contracted for a particular line or subscriber loop, such as a residential phone line, associated with the first party. Typically for an additional charge, the service provider will maintain a list of blocked telephone numbers on behalf of the first party and will examine the caller telephone number of all inbound calls. According to the screening options configured for the first party, an inbound call may be prevented if it meets, or fails to meet, certain criteria. In addition to blocking inbound calls from specific originating numbers, screening options may be configured to similarly block calls wherein the caller number is unknown, unrecognized, or not a member of a specified set.
A special type of call screening has recently become available in conventional residential telephone service wherein any inbound calls, or at least any that do not convey caller identification, are first greeted by an automated system which instructs the caller that the called party does not accept unsolicited calls. In many cases, this is primarily intended to stop telemarketing “cold calls.” Such a system may then invite the caller to record a name to be announced to the called party so that the called party may accept or decline the call. Alternatively or additionally, the screening system may solicit a special numerical code from the caller to allow the call to go through. The numerical code is given to the caller by the called party in advance of the call. For example, a special code may be given to family members so they may satisfy the screening function. In some implementations, when a family member calls from their home and the caller identification is provided, the system may forego such screening. However, screening measures are still invoked whenever the family member calls from a different location, such as a place of employment.
This method of screening is cumbersome and, in many circumstances, equally inconveniences all inbound callers and delays call placement. Even where the use of numerical passcodes allow some trusted parties to traverse the screening mechanism, this burdens desirable callers with having to remember perhaps many such codes associated with various family members. Furthermore, there is no real differentiation of explicitly blocked callers, either by originating telephone number or other means, to ensure that call attempts by such callers are not troublesome to the called party. For example, an unwelcome caller may repeatedly access the call screening system and record a name announcement, whereupon the system will then ring the called party's telephone line and convey the recorded name.
When a called party subscribes to such a screening feature, the choices of disposition are limited and the handling options are provisioned by the telephone service provider. The party may not freely and easily alter the designation and desired handling of blocked calls.
A fundamental difficulty with all manner of prior art call screening approaches is that, when a particular caller is blocked, the caller is not notified that the call has been blocked. The caller will simply receive the same busy signal as if the line were simply occupied with another call. Consequently, the caller may make repeated attempts to reach the called party, unaware that such attempts will be futile. Continued attempts may waste time or resources of the service provider or the parties. It is conceivable that this wastefulness may be compounded if the calling party is able to invoke any form of an automatic retry feature.